256000400 has 90 divisors (see below), whose sum is σ = 637817622. Its totient is φ = 98739200.

The previous prime is 256000391. The next prime is 256000403. The reversal of 256000400 is 4000652.

It can be written as a sum of positive squares in 9 ways, for example, as 151388416 + 104611984 = 12304^2 + 10228^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256000403) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 336020 + ... + 336780.

It is the magic constant of a 800 × 800 magic square.

Almost surely, 2^256000400 is an apocalyptic number.

256000400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256000400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (318908811).

256000400 is an abundant number, since it is smaller than the sum of its proper divisors (381817222).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256000400 is a wasteful number, since it uses less digits than its factorization.

256000400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 837 (or 797 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 256000400 is about 16000.0124999951. The cubic root of 256000400 is about 634.9607514957.

It can be divided in two parts, 256000 and 400, that multiplied together give a 5-th power (102400000 = 40⁵).

The spelling of 256000400 in words is "two hundred fifty-six million, four hundred", and thus it is an aban number.